This paper explains the pipeline simulation techniques TransCanada is proposing to use as a result of new firm short notice services that were recently approved for the Canadian Mainline system. The need for short notice services on TransCanada's Canadian Mainline was triggered by a decision of the Government of Ontario to retire all of the coal-fired electrical generating facilities in Ontario. There is an expectation that much of the lost electrical generating capacity will be replaced by gas-fired generating facilities and the process has already begun with several new gas-fired generating stations being selected. The new power generators have requirements driven by the real-time electricity market that could not be delivered by the suite of services that TransCanada had available. In particular, the power generators needed to have gas deliveries to their plant gate over the range anywhere from zero flow rate to the maximum rate contracted for, on a firm basis all of the time, with the ability to change the rate of consumption on as little as five minutes notice. TransCanada developed two new services that tried to address these requirements, Firm Transportation - Short Notice (FT-SN) and Short Notice Balancing (SNB). For TransCanada to provide these new services in conjunction with all of TransCanada's other services required a way of including the services in the pipeline simulations for capability determination. The SNB service provided particular challenges because it is so distinctive from any other service that TransCanada offers on a firm basis. Being a firm service, TransCanada also needs to be able to justify the construction of new facilities, if required, based on pipeline simulations. The paper provides information regarding how TransCanada will incorporate the new pipeline simulation techniques for short notice services into the existing capacity determination processes. The paper also provides findings regarding the parameters and assumptions that TransCanada has determined are important for pipeline simulations for the new short notice services.
TransCanada's Canadian Mainline System consists of 9,294 miles (14,957 km) of pipeline extending from the Alberta/Saskatchewan border to the Quebec/Vermont border with connections to other natural gas pipelines in Canada and the U.S.
In June of 2005 the Government of Ontario announced an initiative to replace 10 million HP (7500 MW) of existing coal-fired electricity generation. The bulk of the replacement generation capacity is likely to be gas-fired, with much of the new generation capacity located in or near the Greater Toronto Area. It has been estimated that by 2012 the in-Ontario peak day gas requirements for power generation will be in the range from 0.81 Bcf/d (0.86 PJ/d) to 1.27 Bcf/d (1.35 PJ/d) TransCanada also understands that some of the new generation facilities may demonstrate significant fluctuations in gas demand from day-to-day and within the day based on five minute dispatch notifications from the Ontario Independent Electric System Operator.